code: def new_policy_mapping_fn(agent_id, episode, worker, **kwargs):
      return "pol0" if agent_id in ["agent0", "agent1"] else "pol1"
  
file_path: ray/rllib/examples/documentation/saving_and_loading_algos_and_policies.py
imports: from ray.rllib.algorithms.ppo import PPOConfig
  from ray.rllib.algorithms.algorithm import Algorithm
  import os
  from ray.rllib.examples.env.multi_agent import MultiAgentCartPole
  import numpy
  from ray.rllib.policy.policy import Policy
  from ray.rllib.algorithms.ppo import PPOConfig
  from ray.rllib.examples.env.multi_agent import MultiAgentCartPole
  from ray.rllib.algorithms.ppo import PPOConfig
label_desc: Use image node_id 1 for calling a global function with example usage: new_policy_mapping_fn(agent_id, episode, worker) and returns: unknown